Companies are ramping up spending on machines, software, and other productive assets. That's good news for stocks, especially those in the energy, industrial, and technology sectors. Investors should favor Cameron International (ticker: CAM), a maker of drilling equipment; Fluor (FLR), an engineering company; NetApp (NTAP), which specializes in data storage; and KLA-Tencor (KLAC), which leads the market in test equipment for chip makers.